The present invention relates to a waterproof protective cover for protecting a connection part of electrical wires in a waterproof manner.
Conventional arts include protective covers for electrical wires in Japanese Utility Model Publications Nos. 59-119576 and 59-109175.
In Japanese Utility Model Publication No. 59-119576, the protective cover consists of two semi-cylindrical bodies which are pivotably connected to each other by hinges so as to open and close the semi-cylindrical bodies. Each of the semi-cylindrical bodies includes an outer shell and an inner wall arranged inside the outer shell to extend along a periphery of the cover. Inside the protective cover, an inner chamber is defined by the inner wall and an elongated clearance is formed between the outer shell and the inner wall. The protective cover is provided at both ends thereof in the longitudinal direction with openings for passing an electrical wire therethrough. On respective lateral edges of the bodies opposite to the hinges, a pair of latching members are arranged to engage the semi-cylindrical body with the other body. Insulating compound is filled in the inner chamber. In a pre-using state of the cover, thin sheets are arranged on the compounds filled in the respective semi-cylindrical bodies in order to prevent the filled compound from drying and hardening.
In case of using the above-mentioned cover, after tearing off the thin sheets, a connection part of the electrical wires connected to each other by press-fitting or the like is positioned in the inner chamber and then the semi-cylindrical bodies are closed by engaging the latching member to the other member, whereby the connection part can be protected in the cover.
In the above mentioned protective cover, however, the sheets are required for preventing the drying and hardening of the compound. Further, in the cover, when the latching member is engaged with the other latching member, there is a possibility of flowing of the insulating compound out of the inner chamber despite provision of the elongated clearance. Furthermore, since the insulating compound does not harden immediately, even after the sheets have been torn off, there is a problem in that the electrical wires are deviated from a predetermined position by an axial tensile strength onto the wires.
On the other hand, also in Japanese Utility Model Publication No. 59-109175, the protective cover consists of two semi-cylindrical members which are pivotably connected to each other by hinges. Further, each of the semi-cylindrical members is provided at both ends thereof with respective chambers each of which is defined by axial partitions formed in the semi-cylindrical member. In the so-constructed protective cover, since the sealant is supplied in only the chambers arranged at both ends of the semi-cylindrical member, it is possible to reduce an amount of sealant flowing out of the cover when the electrical wire is packed therein, in comparison with that in the previously mentioned protective cover.
However, if the sealant flows out from holes at both ends of the cover, an engagement part of latching members or the like, in even a small amount, a clearance is produced about each electrical wire, so that there would be a problem of intrusion of water into the cover through the clearance. Therefore, this protective cover has a waterproof function inferior to that in the previous protective cover in which the insulating compound surrounds the electrical connection part of the wires directly.